The proposed Program Project on Molecular Immunology of Sexually Transmitted Diseases is a consortium that continues the longstanding and productive interactions between the University of Washington and the leading Canadian and African centers for STD research--the Universities of Manitoba and Nairobi, and draws additional expertise in basic immunology and host responses to infectious diseases from formal collaborative arrangements with Seattle Biomedical Research Foundation, Virginia Mason Research Center, and Puget Sound Blood Center. This program will integrate the expertise of microbiologists, immunologists, molecular biologists, and pathologists in the examination of the molecular basis of the host, immune response to five important STD pathogens--Chlamydia trachomatis, herpes simplex virus and Treponema pallidum. These specific pathogens cause the greatest morbidity in women and children, with serious sequelae including pelvic inflammatory disease and infertility, cervical cancer, and perinatal morbidity and death. The new initiatives of this program include three well-integrated Projects and three Cores, which emphasize state-of- the-art immunologic and molecular techniques. The formal contributions of basic immunologists and infectious disease experts as co- investigators/consultants/collaborators on individual projects and as members of Advisory Committees will serve to enrich the program with the experience and expertise of investigators not working previously in the field of STD's.